Boiler.



1,1. W. JACOBS;

BOILER.

APPLICATION FILED 1123.21, 1a1s.

Patented Apr. 14,1914,

5 SHBETSr-SHEET 1.

1" N\ My k R 1% N W m mm in Na NM 33 mm a H. W. JACOBS.

BOILER.

} APPLICATION TILED APR. 21 1913. 1,093,430, Patented Apr. 14, 1914. 5SHEETS-SHEET 2.

Q Q Q Q WI 'INL'SSES: IN VEN TOR.

H. W. JACOBS.

BOILER.

APPLICATION FILED APR. 21, 1913.

Patented Apr. 14, 1914.

6 SHEETS-SHEET 3.

INVENTOR- 4% A TTOR H. W. JACOBS.

BOILER.

APPLIGATION FILED APR.21,1913. 1,093,430. Patented Apr. 14, 1914. aslums-511311154.

i? 57 37 i 57 57 59 204i,

WITNESSES: INVENTOR- wimwwn Q g Q H. W. JACOBS.

BOILER.

APPLICATION FILED APR. 21, 1913.

Patented Apr. 14, 191.4;

6 SHEETS-SHEET a.

INVENTOR.

WITNESSES.-

(was;

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BOILER.

Specification of Letters Patent.

Patented Apr. 14L, 1914:.

Application filed April 21, 1913. Serial No. 762,634.

To all whom it may concern:

Be it known that I, Hnxnr W. JACOBS, a citizen of the United States, andresident of Topeka. in the county of Shawnee and State of Kansas, haveinvented certain new and useful- Improvements in Boilers, of which thefollowing is'a description, reference being had to the accompanyingdrawings, which form a part of my specification. My invention relates tosteam boilers more especially adapted for marine service; having for itsobject the provision of a boilerwhich will possess greater strength thanthose heretofore employed, by reason of the fact that the structuralmaterial com prisessub-divisions of short transverse sec tions having ashape best suited to with stand the strains to which the same aresubjected.

l Another object of my invention is the provision of a constructionwherein the possibility of violent explosions will be eliminated, notonly due to the greater strength resulting from the peculiarconstruction just referred to, but also because of the fact that with myimproved construction no stay or rivet heads are exposed to the actionof the fire or hot gases either on the crown or side sheet of thefurnace nor in the com bastion chamber or chambers, as, however, is thecase in the ordinary constructions heretofore employed wherein the stayor rivet heads burn off when the same are overheated and thereby allowthe sheets to collapse.

A further advantage of my invention lies in-the fact that in case arupture should occur in any one of the number of sections of which theboiler isconstructed, it cannot spread to the adjacentsection orsections, but on the other hand such break or rupture will be confinedto a small space or area and the steam allowed to escape gradually, andtherefore without disastrous effects.

' A further object of my invention is to provide a boiler the costwhereof will be materially cheapened as well as the cost ofmaintenance,because the worlcof repair or replacing' of worn parts willbe simplified, owing to the possibility of-producing inter "changeableparts by macl'lineryin large quantities p "Another ob ec t of myinvention-1s to proa vide a construction wherein the bad and seriouseffects due to unequal expansion and contraction of the structuralmaterial, re-- sulting from uneven or changing temperatures, will beeliminated, by reason of the flexibility of the construction, attainedthrough the employment of subdivisions or sections of curved crosssection, whereby each sectionis allowed to bend or flex withouttransmitting any great strain to the adjacent sections or parts.

With my improved construction, all stay bolts and rivets are removedfrom the areas of intense heat,-both in the furnace and combustioncha1nbers,-and all seams are produced in the water-space of the boilerwhere they are submerged; at the same time, a construction is providedwherein all the parts are easily accessible for removal, in spection,and repairs or replacement; a construction which also results in a lowmaintenance cost because of the elimination of the bad eiiects due tounequal expansion and stay bolt troubles heretofore encoun tered.

, A further advantage in the employment of my improved constructionexists in the fact that a greater firebox volume is produced with theresult that better combustion is promoted; a greater percentage ofheating surface exposed to the direct ra' diation of heat is obtained,which results in a greater steam capacity. The heating percentage isgreatly increased because of the fact that with my improved constructionI am enabled to use thinner sheets of material in the walls of thefurnace and combustion chambers without, however, sacrificing strength.

My invention results in a construction especially adapted to theapplication of automatic stokers and automatic ash handling systems,which results in great advantages due to the fact that cheaper fuel maybe used, and,thcrefore, fuel and labor cost would be materially reduced,and yet atthe same time obtain av more uniform temperato less hardship,as will be more fully understood from the following detaileddescription.

In the drawiugs:l igure 1 is a longitudinal sectional view of a doubleended boiler equipped with two furnaces at each end thereof; the viewbeing taken on the lines a-a of Figs. 2 and 3, looking in the directionof the arrows. Fig. 2 is a vertical cross sectional view taken on theline b?) of Fig. 1, looking in the direction of the of Fig. 1; the lefthand portion of Fig. 5 is a sectional view. taken on the line ee of Aopen atthe bottom instead of being com- Fig. 4. looking in the directionof the arrows; while the right hand side of Fig. 5 is E "a correspondingflange 13 formed on the boiler heads 14. All of the furnaces A ter--minate ,,at their'iiinner" endsin combustion chambers B. The combustionchambers B a sectional view taken on the line f-f of Fig. 4, looking inthe directionof the an rows.

In the exemplification of I illustrate a double ended boiler? of the drybottom type, provided with two furnaces at each end thereof; that is,the boiler'may be fired from both ends, and the furnaces are pletelysurrounded by a'water-wall or jacket as is the case in the usual wellknown type of marine boiler. The construction as shown in Figs. 1 to 3,therefore,.contemplates four furnaces as indicated at A; two furnacesbeing situated at each end of the boiler and arranged side by side, asmore clearly shown in Fig. 2. 'The furnaces are formed of channelsections 6 which are' preferably substantially U-shape in cross-sectionand the sections of approximate U-shape contour, as clearly shown inFig. 2. The convex surfaces of the sections are presented inwardly,thatais toward the furnace side, so that the flange portions of adjacentsections will be brought substantially parallel to each other -andpermit of their being riveted together on the water-side of the boiler.

Before the flange portions of the adjacent sections are secured inplace, I insert stay- 5E; tions 6 of the-one furnace to those of thesheets as indicated at 7 between the flan es of adjacent sections andthen rivet the adjacent, flanges of the sections and stay-sheets inplace,- as clearly indicated at 8. These stay-sheets 7 are so formed asto tie the secadjacent parallelly arranged furnace, at the longitudinalcenter of the-boiler, as more clearly shown in Fig. 2; and thesestaysheets also tie the furnace-sections 6 to the outer boiler-shell 9,as clearly shown in Fi 2. I prefer to cut away the stay sheets over the'top of the furnace A so as to form projeetingreinforcing webs ofsubstantiallythe same contour as the crowns of the fur- 66 naces A, seeFig. 2. The bottom ends of my invention as shown in F igs. 1, 2, and 3,of the drawings,

each of the furnace-sections 6 are flattened as clearly shown at 6*, inorder to permit the sections to be riveted to the mud rings 10, whilethe joints between them are preferably welded.

The outer ends of the furnaces A are closed by the door-sheets 11, seeFig. 1, which are of the same outside contour as the furnace-sections 6.These door-sheets 11 are riveted near their side edges to the flanges ofthe adjacent furnace-sections with a staysheet 7 interposed, aspreviously described with reference to the furnace-sections; whilethe-bottom edges of the door-sheets are riveted to the'mud-rings 10. Thedoorshcets 11 are provided with door hole flanges as indicated at 12,see Fig. 1, which are secured, in any suitable-manner, as for ex ampleby means of patch belts or rivets, to

are also formed of channel sections 15, subjstantially U-shape in crosssection, similar to the furnace-sections, with the flanges of thesections extending outwardly and into the waterspace of the boiler. Theflanges of-.- the furnace-sections 6 adjacent to the combustion chambersB are of increased di mensions and arranged to extend upwardly so as toform the combustion chamber fluesheets 16, see Fig. 1. The differentsections of the combustion chambers are rivetedtogether with thestay-sheets 17 interposed between them, as clearly shown in Figs. land3. The stay-sheets 17 are so formed as to tie the adjacent parallellyextending combustion chambers B to each other and also tie thecombustion chambers to the sides and bottom of the outside boiler-shell9. j The sides or flan es of the combustion chamber sections 15 adjacentto the inner ends of the furnaces A extend downwardly and form the innerend sheets 18 of the furnaces A; and the bottom ed es of these flangesof sheets 18 are rivete to the mud rings 10 as very clearly shown inFig. 1.

Interposed between the ends of fur naces A and the combustion chamber B,I place stay-sheets 19 which serve't'oftie the outer sides of thefurnace-sections 6 adjacent sides of the sections Sand sectionsl5 tothose of the adjacent and 'parallelly arranged furnaces A and combustionchambers B. -The combustion chamber flue sheetslfl are riveted neartheir top and side edges to the flanges of the adjacent combustioncham-'ber sections with the, intervening; staysheets 19.

. The stay-sheets 17 and 19 are cutout chambers B; and these webs overthe crown of the combustion chambers B soas to form upwardly extendingreinforcing webs of substantially the same general. contour as the topof the combustion are provided with; projecting portions or eyes atintervals, to 'whiclrthc removable stays 20 are attached by means of theusual pins and cotters, or any other suitable means. These removablestays 20 serve to support the crowns of the combustion chamber B fromtheoutside boiler-shell t) as the stays 20 have their upper ends securedby pins and cotters, or any other suitable means, to thereinforcingplates 21; the reinforcing plates 21- being provided with projectingportions atproper intervals to receive the pins where by the stays2O areheld in place. The reinforcing plates 21 are secured in place in amanner to be hereinafter set forth.

,The inner ends of the combustion chamhers B are closed by heads 22,which heads are composed of straight channel sections 23. as moreclearly shown in Figs. 2 and 3. These channel sections are substantiallyU- shape in cross section and arranged with their flanges presentedovtwardly, between which arc placed stay-sheets 24; the staysheets andadjacent flanges being riveted together. The slayshccts 24 tie the heads22 of the oppositely disposed combustion chamhers E8 of the boilertogether. The ends of the channel sections 23 are cut oil so as to makethe contour of the combustion cham- 'tber heads correspond with thecontour of the-combustion chambers B; and the ends ofthe channelsections 23 are flattened out, as clearly shown in the drawings, so asto permit'their being rive ed to the adjacent flange of the combustimichamber section 15 with an' intcrposed stay-sheet 17.

The flue sheets 16 and the boiler-heads 14 .are'providcd with apredetermined numwhile their tops and side bergof holes to receive thetitles 23 which may be welded in place, or secured in any other suitablemanner. The lines 2? serve to convey the gases or products of combustionfrom the .con'ibnstion chambers B to the exteriorof thc boilcr; thefines 25, as clearly shown, being arranged over the tops of the furnacesA.

The boiler-heads 14 are so cut that perin'ieters thereof sidc contour ofthe the (OI'IGSPOIM to the outad acent ends or sides of the adjacentsections of the outside boil rshell th The bottom edgcs of theboilbrheads 14. arc'rivcted to the mud-rings 10. edges are riveted tothe flanges of the adjacent outside sheilsections 26 of which theoutsideboiler-shell t) is'compostah The boiler-heads are riveted 'to theadjacent shell-sections 26 with the "well as rclnforcing plates opposite"ends of the boiler are tied or held together by the stay rods 28, whichare fastened to the boilerheads 14 by means of the usual nuts and*ashers common to marine practice, or by any other suitable mechanism.The boilerheads 14 are preferably both provided with suitable man hplesas indicated at 25), whereby access to the interior of the boiler may behad. The boiler-heads 1-1 are also tied to the door-sheets 11 of thefurnaces A by stay-bolts 30, see Fig. 1; and the door-hole flanges 13,provided on the boiler-heads 14, engage with the corresponding flanges12 formed 011 the furnace door-sheets 11; being secured thereto aspreviously described by means of the usual patch bolts.

As before stated, the outside boiler-shell 9 consists of a series ofchannel sections 26 with their sides or flange portions presentedoutwardly, while the intermediate or inain portions of the sections arecurved so as to present the convex side to the outside of theboiler-shell as very clearly shown in Fig. l. The channel sections 26are so formed that the side edges or flanges will extend outward fromthe convexcd side of the sections as clearly shown in Fig. 1; and inthat respect differing from the formation of the furnace and combustionchamber sections (3 and 15 respectively, where the 95 sides orflange-portions extend-from the conca vcd side of the sections. Thesections 2th, are so arranged that the outwardly extending flangesthereof will be ar 'anged parallel with each other so that they may berivet loo ed together with the stay-sheets 7 inter posed between them aswell as the inwardly extending reinforcing plates 27; the latter beinginserted between the adjacent sections 26 at a point above thestay-sheets 7 as 105 very clearly shown in Figs. 1 and 2. Thereinforcing plates 27 are then preferably welded to the stay-sheets 7 atthe point indicated at 31;, see Fig. 2.

The outside boiler-shell sections 32, which 11.0 surround the combustionchambers B, are composed of channel sections, similar in cross-sectionto the cross-section of the sections 26 except that thesections 32 havea circular contour. These sections 32 1 are secured together in a mannersimilar to that ofsections. 26, by having the stay-sheets 17, as well asthe inwardly extending reinforcing plates-21, interposed, see Fig. 3.The reinforcing plates 21 are 1 inserted between the sections 32 abovethe stay-sheets 17; and the various sections as well as the stay-sheets17 and reinforcing and their abutting'ends Welded together at ter theyhave been placedin position.

In order that the U-shape portions and the circular portions or sectionsof the outside boiler-shell 9, namely the portions which surround thefurnaces and the portions which surround the combustion chambers, may beconnected together, I provide the throat-sheets 33. These throat-sheets33 are preferably formed in two parts, with the upper portion consistingof a semi-circular channel section substantially similar incross-section to the sections 26 andQ/T. The upper and lower portions ofthe throatsheets 3.3 are welded together after they have been placed inposition. The throatsheets are provided with flanges, one of which ismade to conform with the contour of the. adjacent section 26, that isapproximately of the U-shape contour of the outside boiler-shell 9, andis riveted to the flange of the adjacent section 26 with the interposedstay-sheets i9 and reinforcing plate 27. The other or opposite flange ofboth throat-sheets 33 is made,t .eonform with the contour of theadjacent o ilside shell-section 32, that is of circular contour, and isriveted to the flange of the adjacent section 32' through theintervening combustion chamber stay-sheets E24 and reinforcing plate 21.

. The bottom edge or fiange of the throatsheet 33 is riveted to themud-ring 10, as clearly shown in Fig. l; and stay-bolts 3i tie thethroat-sheets 33 to the furnace interior end-sheet 18 which, in theconstruction illustrated, is formed integral with the combustion chambersection 15 which lies adjacent to the fiu'nace-section 6. In order thatthe inner end-sheets 18 o the oppositely disposed furnaces A may bemaintained against internal pressure and "be prevented from bulging, Iprovide the stay-rods 3.3 which extend longitudinally of the furnacebeneath the. combustion chambers B and have their ends suitably securedtoQthe furnace end-sheets 18 of oppositely disposed furnaces A, asclearly shown in Fig. 1. The parts of the boiler-heads it. and thethroat-sheets 33 which are not braced by stay-bolts, I reinforce by theadditional stay-rods 36, seeFig. 2. which tie the boiler-heads 14 andthe throat-sheets 33 to-- gether; the ends of the rods being secured inany suitable manner.

I have. shown and -described a boiler having four furnaces. two of whichare located at each end of the boiler, and the furnaces provided withseparate combustion chambers; the invention, however, permits of avariety of modified forms; as for example,

the. invention may be applied to either 1 single or double ended boilerhaving one or -1norc furnaces at each end; furthermore each furnace mayhave a separate combustion chamber, or two or more furnaces at one endof the holler. may open into. a common combustion chamber; or two ormore furnaces situated at opposite ends of the boiler may open into acommon combustion chamber.

In Figs. 4 and 5, I illustrate a modified form of my invention, thefigures disclosing a single ended dry bottom boiler provided with asingle furnace. The construction portions-of the various sections arepresented outwardly so as to permit of their being secured or rivetedtogether outside of the furnace so as to come in the water-portion ofthe boiler. Before the various sections are riveted together, I preferto insert staysheets 7", so arranged as to extend somewhat beyond thecdges of the flange portions. These stay-sheets are cut away over thetop of the furnace C so as to form upwardly extending reinforcing webswhich are preferabl provided at intervals with eves whereby removablestays 37 may be at-- tachcd thereto by means of pins and cotters, or inan y other suitable manner. The

.rcnn 'able stays 37 serve to support the crown of the furnace C, as theother ends of the stays are attached by'pins and cotters, or in anyother suitable manner, to eyes or outside boiler-shell 39.

The stay-sheets 7 5 at the sides of the furnacecare cut out at intervalsso as to allow for the horizontal circulation of the water.

Intermediate of the cut-out portions. I preferably provide thestay-sheets 7 with oval heads on their outer edges whichare adapted tofit into corres1uuuling sockets-cut into the T-irons l0. (see-Fig. 5),which are riv eted to the outside boiler-shell. v

The outer end of the furnace C is closed by a door-sheet 11, see Fig."i, which is'given the same contour as the furnace-sections 6. Thedoor-sheet ll is riveted at its top and side edges to the flange of theadjacent furnace-section (1" with an interposed staysheet 7: while thebottom edge of the door sheetjs riveted to the mud-ring 10; and thesheet 11 is provided with a door-hole flange 12. The inner end of thefin-mice C terll'lllliltfltlfl a combustion chamber D which is composed.of channel sections 15. These channel sections are substantially,Ushape 1n cross section and of curvilinear contour a members which areshown riveted to the veryclearly shown in'Fig. 5. The flange thefurnzwe-section 6 adjacent to the combastion chamber D is formed so as"to xtend upwardly and provide the fiue-sheet 1t) adjacent to the furnaceG, extends downwardly and forms the inner end-sheet 18 '-of the furnace,and this inner end-sheet is riveted to the mud-ring 10 located adjacentthereto.

h'stay-slieet 19 is inserted at the juncture of the furnace C and thecombustion chamber D, that is intermediate of the flanges of theadjacent sections, and the .stay-sheet, together with the combustionbetween the sections as to form outwardly extendmg 'webs on thecombustlon chamber chamber flue-sheet 16. is then riveted to theadjacent combustion chamber section 15 along its top and side edges. Thefurnace inuer-end sheet 18 is riveted along its side edges to the flangeof the adjacent furnacesections 6 with the stay-sheet 19 interpcsedbetween; and that part of the staysheet 19 which isriveted between thefurnace inner-end sheet 18 and the adjacent furnace section 6 is made toconform with the corresponding part 'of the stay-sheet? at the sides ofthe furnace C; while the part that is riveted between the combustionchamand forms a projecting reinforcing web which is provided withprotrusions or eyes to which the removable stays 20 are secured. Thecombustion chamber sections 15 have their adjacent flanges rivetedtogether with interposed reinforcing plates 41 between, which are giventhe same general contour as the combustion chamber sections 15. Thesereinforcing plates 41 are so secured D; and the plates are provided.with eyes at proper intervals to which the removable stays 20 aresecured whereby the combustion chamber D is supported from the outsideboiler-shell 39; the stays being attached in any suitable manner as forexample by pins and cotters. The opposite ends of the removable stays 20are secured in a similar mannerto eyes42 which are riveted to theoutside boiler-shell 39.

The rear end of the combustion chamber 1); that is the end opposite tothe furnace opening, is closed by a head 22? which is composed ofstraight channel sections 23 "'"as more clearly seen 111 Fig. 5; thechannel sections 23 being substantially U-shape in cross-section, withtheir convex sides presented inwardly; while the flanges of therespective sections *are riveted together with stay-sheets 24:interposed between them.

The stay-sheets 24; are provided at their outer edges-with heads of ovalcross-section,

and are cut away at intervals'to allow for the horizontal circulation ofthe water. The

heads of the staysheets 24 are held in cor- .ter are ,rivetedto theboiler-head 44. At

combustion chamber section 15 with an. in

tervening reinforcing plate it. e

The flue-sl1eet 16, as well :is the back boiler-head 45, are providedwith suitable holes to receive the ends of the has 25, which arepreferably welded in place. The flues, as clearly shown in the drawings,extend over the top of the furnace C and serve to carry the gases orproducts of combustion. from the combustion chamber D to the exterior ofthe boiler. The back boiler-head 45 is cut and flanged to conform\vith'the contour of that part of the outside boilershell 39 surroundingthe furnace C, and the head 45 is riveted to the outside shell along itstop and side edges, while the bottom edge bolts. The back boiler-head 45is tied to the furnace door-sheet 11 by staydoolts 30. The backboiler-head 4-5 is also tied to the front boiler-head 44 by stay-rods 28which are secured by means of the usual nut and washer. common in marinepractice, or in any other suitable manner.

The outside boiler-shell 39, in'thc construction shown in Figs. 4 and 5,is preferably composed of dilferent parts; with the upper or crownportion 39 preferably made semi-cylindrical and extending the'fulllength of the boiler, and the. ends thereof riveted to the b-oilcnheads44 and 45 as clearly shown in Fig. 4; while the side portions 39, of theoutside boiler-shell, and which inclose the sides of thc'furnace .C, arepreferably composed of fiat sheets riveted at their bottom edges to themud-rings 10; their upper edges being riveted to the upper: or crownportion of the boiler-shell.

. plate'46, thus providing a horizontally disposed web or rib. The edgesof the side portions 39 are riveted to the back boilerhead 45, While theopposite edges are riveted to the throat-sheet 33.

In order that the flat portion of the side sheets 39* above thestay-sheets 7-of the furnace may be braced against internal pressure, Iprovide bracing means preferably inithe form of T-irons 17, see Fig. 5,which re riveted to the inside of the side. sheets and have removablestays at} secured thereto by pins and cotters, or any other suitablemeans; while the other ends of the stays ,48 are secured in a similarman- I may be braced and firmly secured in place,

I provide the stay-bolts 34 which are secured to the throat-sheet and tothe inner end furnace-sheet 18. ing about the bottom half of thecomb'ustion chamber D is preferably semi-circular in cross-section andis riveted by means of outwardly extending flanges, with the interposedreinforcing plate 46, to the corresponding flanges on the crown-sheet 39of the outside boiler-shell. The furnace innerend sheet 18, which is notbraced by the stay-bolts 34, is preferably tied to the outsideshell-sheet 49 by stay-rods 50, secured at their ends in any well knownmanner; and the parts of the front boiler-head 44,

' not stayed by the combustion head stays 24,

are braced to the outside shell-sheet 49 by the stay-rods 51, see Fig.4.

The boiler-heads are shown provided with man-holes 52 whereby access tothe interior of the boiler may be readily had.

From the drawings and foregoing description, it is apparent that themethod of construction illustrated in Figs. 4 and 5 possesses anadvantage in that the outside boiler-shell can be. easily removed forinspection and repairs or replacement, as the crown-sheet 39 can bereadily removed by driving out the rivets in the longitudinal flanges atthe sides of the boiler,-and which extend through the horizontallydisposed reinforcing web or plate 46, and the rivets which secure thecrown-sheet to the boiler-heads 44 and 45, and then disconnecting theremovable stays 37 and 20 The same is true with reference to theinclosing sheet 49 secured about the lower half of the combustionchamber D, as by removing the rivets in the joints between the sheet 49and the crown-sheet 39*, removing the rivets connecting the sheet 49 tothe front boilerhead 44 and to the throat-sheet33, will permit thestay-rods 50 and 51 to be disconnected and thereby give access to thispart of the boiler. I outside boiler-shell can be readily removedbydriving out the rivets along their edges, disconnecting the stays 48,after which the side sheets39 need only belifted up or down slightly torelease the oval heads on The sheet 49 extend-' The side sheets 39*" ofthe the stay-sheets 7 a from the sockets formed in the T-irons 40; whichwill permit the sheets to be removed from the boiler, -The frontboiler-head 44 can readily be removed in the same manner afterhaving-been disconnected from the outside boiler-shell 39, and either"the crown-sheet 39 orthe lower sheet 49 having been removed from theboiler, so as to allow the boiler-head to be moved vertically and permitthe releasing of the heads of the combustion chamber head stay-sheets$34 from their sockets in the T-irons 43.

This method will allow these parts to be removed without destroyingtheir respective stay members. The back boiler-head 45, as well as thethroat-sheet 33, are removed in the usual way by driving out the rivets,cutting out the stay bolts, and disconnecting the respective stay-rods.

Theconstruction as shown in Figs.'4 and 5, like the construction shownin the preceding figures, permits of a variety of modifications in thearrangement of the furnaces and combustion chambers without, however,departing-from the principle of my invention. For example, theconstruction may be made either as a single or a double ended boil'erhaving one or more furnaces at each end; each furnace may be equippedwith a separate combustion chamber, or two ,or more furnaces at the sameend of the boiler may have a common combustion chamber; or two or morefurnaces at opposite ends of the boiler may have a common combustionchamber.

In operation, the flames and products'of combustion pass from thefurnaces A and C, in the constructions shown in Figs. 1 and 4, to thecombustion chambers B andfD respectively, and from there they areconveyed by the fiues 25 and 25*, respectively, to the exterior of theboiler through the boilerheads 14 and 45 respectively, to which hoods oruptakes are attached whereby the smoke is conveyed to the smoke stack. a

:I have shown and described What I believe to be the best forms of myinvention; but as previously stated, the same may be modified in certainrespects Without, however, departing from the spirit of my invention,and I do not wish to. be understood,

therefore, as limiting myself to the exact constructions shown.

What I claim is 1. In a boiler of the class described, a furchamberbeing eloi'igated upwardly to constitute an integralflue sheet andsecured to the flange of the adjacent combustion cham ber' section onthe water side of the boiler.

2. A boiler, composed of one or more fire-- nace section adjacent to thecombustion j boxes and oue'or more.combustion chambers K arranged atopposite ends of the boilerjwith the combustionchambers arrangedadjacent to the vertical center line bf the boiler, the tire-boxes andcombustion chambers being, composerbot' sections substantially U-shapein cross section, having their flange portions 'irescnted outwardly,with the flange portions of the adjacentfire-box sections and combustionchamber sections elongated upwardly and downwardly, respectively, so asto provide integral flue sheets and tire-box inner end sheets adapted tobe secured to the adjacent flanges on the water side of the boiler.

3. A dry bottom boiler of the class described, the furnace portion andcombustion chamber portion being composed of channel sectionssubstantially U-shape in cross sec: tion, the furnace portion beingofapproxi mate U-shape contour, the flange of'the furnace' sectionadjacent to the combustion prising furnace portions and combustionchamber portions arranged on opposite sides of the vertical center lineand longitudinal center line of the boiler, the furnace and "combustionchamber portions beingcom- 40 posed of subdivisionssubstantially U-shapcin cross sectlon with their ad acent sides or flange portions presentedoutwardly and secured together, the flange portions of the furnacesections adjacent to the combustion chamber portions being presentedupwardly to constitute combustion chamber flue sheet-s,

while the combustion chamber section flanges adjacent to the furnaceportions arepre sented downwardly to constitute furnace inner endsheets, the inner endsof-the combustion chamber portions being providedwith heads composed of channel sections having their flanges presentedoutwardly, and stay sheets intermediate of the sections composing theadjacent walls of furnaces are ranged at the same end of the boiler andbetween the sections of oppositely disposed combustion chambers wherebythe adjacent walls-of. the furnaces and of the combustion chambers aresecured together,

A boiler of the class described, provided with two furnaces at each endthereof and with combustion chambers intermediate of the inner ends ofthe furnaces, the furnaces and combustion chambers being composed ofsectionssubstantially U-shape in cross section. with the flanges of'thefire-box sect-ions "adjacent to the combustion chainhers being extendedupwardly to constitute flue sheets integral with said fire-box sec-'tions, all of the sections being secured together on the Water side ofthe boiler, and stay sheets secured intermediate of the sections of thedifferent furnaces and combustion chambers whereby the sections arereinforced, with the stay sheets intermediate of the sections of thefurnaces arranged at the same end of the boiler being adapted to tie thesections of the parallelly arranged furnaces together and provide anintervening water leg.

A boiler of the class described, comprising a furnace portion and acombustion chamber portion. the fnrnace'and combustionchambeiportionsbeing composed. of sections of curved .cross section with the sides orflange portions of the different sections being presented outwardly.stay sheets secured intermediate of the flange portions or sides of thedifferentsections whereby the furnace and combustion chamber portionsare reinforced. the stay sheets being cut away to conform to thecontour-of the crowns of the furnace and combustion chamher and permitof free water circulation and to provide projections or eyes at spacedpoints or intervals, stays removably secured to said projections or eyesand to the outer boiler shell whereby the furnace and com bustionchamber are supported, the inner end of the combustion chamber portionbeing provided with a head composed of channel sections substantiallyUshape in cross section having their sides or flanges presentedoutwardly. reinforcing members secured intermediate of the sectionsconstituting the head of the combustion chamber whereby said sectionsare secured to the outer boiler shell, and stay rods intermediate of theboiler-heads at opposite ends of the boiler whereby the boiler-heads aretied to gather.

7. A boiler of the class described wherein the fines extend above thecrown of the fircof the fire-box section adjacent to the combustionchamber being extended upwardly to provide a flue sheet integral withthe firebox section, and the inner end of the combustion chamber isprovided with a head composed of channel sections substantially U- shapein cross section, the flanges of all the sections beingpresentedoutwardly and secured together on the water side of the boiler.

8. A boiler wherein the fire-box and combustion chamber are composed ofsections substantially U-shape in cross section, with their flangespresented outwardly, the

flanges of the adjacent fire-box and combus tion'chamber sections beingelongated in an upward and a downward mannen-respectively, to provideaflue sheet integral with,

combustion chamber provided with a head I com'posed'of' channel sectionssubstantially 'U-shape in cross section,

with the flanges of all the sections presented outwardly andsecuredtogether on the water side of the boiler.

10. In a ,dry bottom boiler of the class described, provided witli oneor more fireboxes at opposite ends of the boiler, and one or morecombustion chambers intermediate of the opposing ends of the fire-boxes,with the fire-boxes and combustion chambers composed of channel sectionshaving their flanges presented outwardly and secured to-.

gether on the water side of the boiler, the flan e of the fire-boxsection adjacent to the com ustion chamber being elongated upwardlytoconstitute an integral flue sheet for the combustion chamber, While theflange of the combustion chamber section'adjacent to the fire-box iselongated downwardly to constitute an inner end. sheet, the combustionchambers being provided with heads composed of channel sections havingtheir flanges presented outwardly and secured together on the water sideof the boiler, reinforcing members intermediate of all of the sectionswhereby the fire-box and combustion chamber sections are supported fromthe outer boiler shell and intervening Water spaces provided, With theportion of said outer chamber made in two semi-circular portionsprovided with abutting ends adaptedto be secured together.

Witnesses:

GEORGE HEIDMAN, R. E. -WIGI-ITON.

shell surrounding the combustion HENRY W. JACOBS.

